package cn.wolfcode.p2p.hosting.util;

import java.io.ByteArrayOutputStream;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;
import java.security.cert.Certificate;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

import javax.crypto.Cipher;

import org.apache.commons.codec.binary.Base64;

/**
 *
 * <p>RSA签名,加解密处理核心文件，注意：密钥长度1024</p>
 * @author leelun
 * @version $Id: RSA.java, v 0.1 2013-11-15 下午2:33:53 lilun Exp $
 */
public class RSA {

    /**
     * 签名算法
     */
    public static final String  SIGNATURE_ALGORITHM = "SHA1withRSA";
    /**
     * 加密算法RSA
     */
    public static final String  KEY_ALGORITHM       = "RSA";
    /**
     * RSA最大加密明文大小
     */
    private static final int    MAX_ENCRYPT_BLOCK   = 117;

    /**
     * RSA最大解密密文大小
     */
    private static final int    MAX_DECRYPT_BLOCK   = 128;

    /**
     * 获取公钥的key
     */
    private static final String PUBLIC_KEY          = "RSAPublicKey";

    /**
     * 获取私钥的key
     */
    private static final String PRIVATE_KEY         = "RSAPrivateKey";

    /**
     * <p>
     * 生成密钥对(公钥和私钥)
     * </p>
     *
     * @return
     * @throws Exception
     */
    public static Map<String, Object> genKeyPair() throws Exception {
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);
        keyPairGen.initialize(1024);
        KeyPair keyPair = keyPairGen.generateKeyPair();
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        Map<String, Object> keyMap = new HashMap<String, Object>(2);
        keyMap.put(PUBLIC_KEY, publicKey);
        keyMap.put(PRIVATE_KEY, privateKey);
        return keyMap;

    }

    public static void main(String[] args) throws Exception {
        Map<String, Object> genKeyPair = genKeyPair();

        String base64publicKey = getPublicKey(genKeyPair);
        System.out.println("公钥 \n" + base64publicKey);
        String base64privateKey = getPrivateKey(genKeyPair);
        System.out.println("私钥\n" + base64privateKey);

        String passwd = "cat123113";
        String charsetName = "utf-8";

        String encryptByPublicKey = Base64.encodeBase64String((encryptByPublicKey(
            passwd.getBytes(charsetName), base64publicKey)));
        System.out.println("加密\n" + encryptByPublicKey);

        byte[] decryptByPrivateKey = decryptByPrivateKey(Base64.decodeBase64("uyzmES9QCqVrNO8KPtoBuFXOf0roJBPpSnAcOO7DUiQqi122S73+oZxe7/sIIIDL13mq2vXBfrfHEIJ4eJW+yM8J7MH6aO///nZXa75wwAOlysRpCfF9pBtNefQ6mnE8RdJeTI3Tq/6bKXQXWi8MDorxWN87E/FnbM1sTASR4CI="),
            "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");
        String string = new String(decryptByPrivateKey, "utf-8");
        System.out.println("解密后\n" + string);
        
        
        
        String text="_input_charset=UTF-8&deposit_amount=361.00&deposit_status=SUCCESS&inner_trade_no=121462435441575330216&notify_id=201605050006405601&notify_time=20160505160420&notify_type=deposit_status_sync&outer_trade_no=052016050516061149749497&version=1.0";
        String sign="S3uVxluuqjjp8hxKuQlaqWe4YFjRKm8t/G83uc7zvhSqgzFH9f65IIZDV7c3PGnP0w9d0UoqlGq4KVGimf5Q8eGHPhqtqs45zWBPdZ7gyBlc0H2bmqPJrZmhSXcw/YlZMiC7lmtFOjXv42jxSsMM/bYD9lVFqK/FmCzCrtbBdXg=";
        String charset="UTF-8";
        base64publicKey="MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDv0rdsn5FYPn0EjsCPqDyIsYRawNWGJDRHJBcdCldodjM5bpve+XYb4Rgm36F6iDjxDbEQbp/HhVPj0XgGlCRKpbluyJJt8ga5qkqIhWoOd/Cma1fCtviMUep21hIlg1ZFcWKgHQoGoNX7xMT8/0bEsldaKdwxOlv3qGxWfqNV5QIDAQAB";
        if(verify(text, sign, base64publicKey,charset ))
        {
        	System.out.println("true");
        }
        else
        {
        	System.out.println("false");
        }

    }

    /**
     * 签名字符串
     *
     * @param text
     *            需要签名的字符串
     * @param privateKey 私钥(BASE64编码)
     *
     * @param charset
     *            编码格式
     * @return 签名结果(BASE64编码)
     */
    public static String sign(String text, String privateKey, String charset) throws Exception {

        byte[] keyBytes = Base64.decodeBase64(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initSign(privateK);
        signature.update(getContentBytes(text, charset));
        byte[] result = signature.sign();
        return Base64.encodeBase64String(result);

    }

    public static String sign(String text, PrivateKey privateKey, String charset)
                                                                                 throws SignatureException,
                                                                                 InvalidKeyException {
        try {
            Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
            signature.initSign(privateKey);
            signature.update(getContentBytes(text, charset));
            byte[] result = signature.sign();
            return Base64.encodeBase64String(result);
        } catch (NoSuchAlgorithmException e) {
            //不可能发生，
            return null;
        }
    }

    /**
     * 签名字符串
     *
     * @param text
     *            需要签名的字符串
     * @param sign
     *            客户签名结果
     * @param publicKey
     *            公钥(BASE64编码)
     * @param charset
     *            编码格式
     * @return 验签结果
     */
    public static boolean verify(String text, String sign, String publicKey, String charset)
                                                                                            throws Exception {
        byte[] keyBytes = Base64.decodeBase64(publicKey);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PublicKey publicK = keyFactory.generatePublic(keySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initVerify(publicK);
        signature.update(getContentBytes(text, charset));
        return signature.verify(Base64.decodeBase64(sign));

    }

    /**
     * <P>
     * 私钥解密
     * </p>
     *
     * @param encryptedData 已加密数据
     * @param privateKey 私钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPrivateKey(byte[] encryptedData, String privateKey)
                                                                                     throws Exception {
        byte[] keyBytes = Base64.decodeBase64(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, privateK);
        int inputLen = encryptedData.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段解密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
                cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_DECRYPT_BLOCK;
        }
        byte[] decryptedData = out.toByteArray();
        out.close();
        return decryptedData;

    }

    /**
     * <p>
     * 公钥解密
     * </p>
     *
     * @param encryptedData 已加密数据
     * @param publicKey 公钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPublicKey(byte[] encryptedData, String publicKey)
                                                                                   throws Exception {
        byte[] keyBytes = Base64.decodeBase64(publicKey);
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicK = keyFactory.generatePublic(x509KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, publicK);
        int inputLen = encryptedData.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段解密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
                cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_DECRYPT_BLOCK;
        }
        byte[] decryptedData = out.toByteArray();
        out.close();
        return decryptedData;

    }

    /**
     * <p>
     * 公钥加密
     * </p>
     *
     * @param data 源数据
     * @param publicKey 公钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPublicKey(byte[] data, String publicKey) throws Exception {
        byte[] keyBytes = Base64.decodeBase64(publicKey);
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicK = keyFactory.generatePublic(x509KeySpec);
        // 对数据加密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, publicK);
        int inputLen = data.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        return encryptedData;

    }

    /**
     * <p>
     * 公钥加密
     * </p>
     *
     * @param data 源数据
     * @param cert 证书
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPublicKey(byte[] data, Certificate cert) throws Exception {

        // 对数据加密
        PublicKey uk = cert.getPublicKey();
        Cipher cipher = Cipher.getInstance(uk.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, uk);
        int inputLen = data.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        return encryptedData;

    }

    /**
     * <p>
     * 私钥加密
     * </p>
     *
     * @param data 源数据
     * @param privateKey 私钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPrivateKey(byte[] data, String privateKey) throws Exception {
        byte[] keyBytes = Base64.decodeBase64(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, privateK);
        int inputLen = data.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        return encryptedData;

    }

    /**
     * @param content
     * @param charset
     * @return
     * @throws SignatureException
     * @throws UnsupportedEncodingException
     */
    private static byte[] getContentBytes(String content, String charset) {
        if (charset == null || "".equals(charset)) {
            return content.getBytes();
        }
        try {
            return content.getBytes(charset);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException("签名过程中出现错误,指定的编码集不对,您目前指定的编码集是:" + charset);
        }
    }

    /**
     * <p>
     * 获取私钥
     * </p>
     *
     * @param keyMap 密钥对
     * @return
     * @throws Exception
     */
    public static String getPrivateKey(Map<String, Object> keyMap) throws Exception {
        Key key = (Key) keyMap.get(PRIVATE_KEY);
        return Base64.encodeBase64String(key.getEncoded());
    }

    /**
     * <p>
     * 获取公钥
     * </p>
     *
     * @param keyMap 密钥对
     * @return
     * @throws Exception
     */
    public static String getPublicKey(Map<String, Object> keyMap) throws Exception {
        Key key = (Key) keyMap.get(PUBLIC_KEY);
        return Base64.encodeBase64String(key.getEncoded());
    }
}
